The invention relates to building construction and particularly to a flashing construction intended to prevent leakage at various joints. While the invention has particular application to geodesic domes structures, it will be understood to also have application to other structures. Geodesic dome structures have been utilized for many years and are being used increasingly as dwelling places. To enclose any given number of feet of floor area, the surface area of the dome will have less surface area than any conventional rectangular structure. This is highly advantageous not only in terms of initial building costs but also in terms of heating costs. Such structures have natural air flows on the inside and offer little wind resistance on the outside. An additional advantage of such structures is that no columns or beams are required for support and accordingly great flexibility in interior design including wall and furniture placement is possible.
The prior art includes Pierrepont U.S. Pat. No. 1,330,609 which discloses a flashing for window and door frames having some general similarity to the apparatus in accordance with the invention. The apparatus differs in that it is intended for construction members which are fixed together at the time of installation of a flashing. In contrast, the apparatus in accordance with the invention is intended for installation on prefabricated assemblies which are then shipped to an assembly site for final assembly.
Such structures have, in the past, been manufactured by assembling a number of triangular sections at a job site and then applying, at the job site, shingles to the exterior surface. This has the substantial disadvantage that the economic advantages inherent in prefabricating individual triangular sections (completed with shingles) is not possible. An additional disadvantage is that the person who is erecting the home must deal with the additional inconvenience of shingling the exterior of the home. This is of greater significance in such homes than in conventional rectangular structures because each of the large number of joints must be very carefully sealed and in addition the individual who is erecting the home may be a "do-it-yourselfer" who does not have extensive experience even in shingling conventional homes. The shingling of triangular sections disposed at a wide variety of orientations is, of course, enormously more complex than the shingling of conventional homes.
The number of joints involved and the complexity of the interfaces between the various sections will be more apparent by consideration of the geometry of a typical dome shaped building. Such homes, in some forms, are manufactured of sixty individual triangular elements. The triangular elements are provided in two basic sizes and interface to define sets of triangular elements which define five pentagons and five hexagons. Individual triangular sections, even with shingles disposed thereon, can be moved by a crew of three men without the requirement for a crane. The triangular sections are bolted at the job site.
It is a primary object of the invention to provide a flashing structure for geodesic dome structures which will enable the application of shingles to individual triangular sections at a central factory.
It is another object of the invention to provide a structure of this type which will facilitate the easy assembly of the prefabricated triangular panels even by those who do not have substantial experience in such assembly operations.
It is another object of the invention to provide apparatus which is simple and inexpensive to manufacture.